Date of Award
1993
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Abstract
The present Ph.D. dissertation was focused on the study of the fluid dynamics of high temperature bubble and slurry bubble columns. The study was centred on a system of particular interest for the petrochemical industry, the liquid phase methanol synthesis process, for which very little information is currently available. Emphasis was placed on the study of important gas phase parameters, including the gas holdup, the bubble rise velocity, the bubble chord length and the bubble chord length distribution, which were measured using spherical bulb fibre optic sensors.;The experiments were conducted in a 0.2 m diameter and 2.4 m height carbon steel column operated in the batch mode with respect to the liquid or slurry suspension. The gas superficial velocity was varied between 2.2 and 14.7 cm/s, while the operating temperature ranged from 25 to 175{dollar}\sp\circ{dollar}C. In order to reliably represent the system studied (methanol synthesis), the exact liquid (paraffinic oil) and solid (ZnO-CuO catalyst) phases encountered in this system were used. Nitrogen was used as the gas phase. The fibre optic sensors (two) were implemented using a newly designed insertion device that allowed flexible and precise radial and axial displacement of the sensors. This device provided the possibility to investigate the bubble characteristics at several locations in the column, including the proximity to the gas distributor and the column wall.;Important information concerning the radial and axial profiles of crucial gas phase properties such as the gas holdup, the bubble velocity, the bubble frequency, the bubble axial chord length and the bubble axial chord length distribution was obtained under a significant range of operating conditions. The information and the mathematical modelling presented in this work unveil important fluid dynamics features of bubble and slurry bubble column reactors, such as the dual cell flow pattern and the bubble "coalescence-break-up" regime. This study contributes, in this sense, to a better understanding of the complex fluid dynamics and mixing patterns encountered in bubble and slurry bubble columns in general, while providing reliable data for a number of systems of prime interest for the petrochemical industry.
Recommended Citation
Chabot, Julie, "Fluid Dynamics Of High-temperature Bubble And Slurry Bubble Columns" (1993). Digitized Theses. 2224.
https://ir.lib.uwo.ca/digitizedtheses/2224